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Consistent Presence (consistent + presence)
Selected AbstractsHomogeneity of active demyelinating lesions in established multiple sclerosisANNALS OF NEUROLOGY, Issue 1 2008Esther C. W. Breij PhD Objective Four different patterns of demyelination have been described in active demyelinating lesions of multiple sclerosis (MS) patients that were biopsied shortly after disease onset. These patterns were suggested to represent heterogeneity of the underlying pathogenesis. The aim of this study was to determine whether lesion heterogeneity also exists in an unselected collection of autopsy material from patients with established MS. Methods All MS brain tissue available in the VU Medical Center was assessed for the presence of active demyelinating lesions using magnetic resonance imaging,guided sampling and immunohistochemistry. Tissue blocks containing active demyelinating lesions were evaluated for the presence of complement and antibody deposition, oligodendrocyte apoptosis, differential loss of myelin proteins, and hypoxia-like damage using histology, immunohistochemistry, and confocal microscopy. Blocks with active demyelinating lesions were compared with blocks with active (nondemyelinating) and inactive lesions. Results Complement and antibodies were consistently associated with macrophages in areas of active demyelination. Preferential loss of myelin proteins, extensive hypoxia-like damage, and oligodendrocyte apoptosis were absent or rare. This pattern was observed in all tissue blocks containing active demyelinating lesions; lesion heterogeneity between patients was not found. Interpretation The immunopathological appearance of active demyelinating lesions in established MS is uniform. Initial heterogeneity of demyelinating lesions in the earliest phase of MS lesion formation may disappear over time as different pathways converge in one general mechanism of demyelination. Consistent presence of complement, antibodies, and Fc, receptors in phagocytic macrophages suggests that antibody- and complement-mediated myelin phagocytosis is the dominant mechanism of demyelination in established MS. Ann Neurol 2008;63:16,25 [source] The influence of pre-fermentative practices on the dominance of inoculated yeast starter under industrial conditionsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 5 2002Maurizio Ciani Abstract The influence of pre-fermentative practices on the growth dynamics of a ,natural' starter culture with specific phenotype (H2S,) concurrently with wild yeast populations was evaluated under winery conditions. Different clarification procedures and added SO2 strongly influenced species and cell numbers isolable at the pre-fermentation stage. Independent treatments of must with sulphite addition or vacuum-filtering clarification caused a 30-fold reduction in viable cells. Clarification procedures, enhanced by the selective effect of SO2 addition, induced the appearance of Saccharomyces cerevisiae ,wild' yeasts. Correct application of the inoculum generally guarantees the dominance of fermentation by starter cultures. However, inoculated fermentations using unclarified white and red musts exhibited a consistent presence and persistence of non- Saccharomyces and/or Saccharomyces ,wild' yeasts during fermentation. The extent and composition of the initial wild microflora at the start of fermentation may affect the presence and persistence of wild Saccharomyces and non- Saccharomyces yeasts during guided fermentations under commercial conditions. The above findings confirm the results of previous works carried out at laboratory- or pilot-scale level. Furthermore, they suggest a clear correlation between the modality of pre-fermentative practices and the presence and persistence of ,wild' yeasts during fermentation. © 2002 Society of Chemical Industry [source] Co-localization of von Willebrand factor with platelet thrombi, tissue factor and platelets with fibrin, and consistent presence of inflammatory cells in coronary thrombi obtained by an aspiration device from patients with acute myocardial infarctionJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 1 2006Y. HOSHIBA Summary.,Background:,Detailed histochemical analysis of coronary thrombi obtained freshly from acute phase of myocardial infarction patients may provide information necessary to understand the mechanism of coronary occlusive thrombus formation. Methods and Results:,Coronary thrombi causing myocardial infarction were obtained from 10 consecutive patients of myocardial infarction in the acute phase, using a newly developed aspiration catheter. All the fixed specimens of coronary thrombi, by hematoxylin and eosin staining, were found to contain three major constituents, namely, platelets, densely packed fibrin and inflammatory cells, including polymorphonuclear and mononuclear cells, although their distribution in each specimen is totally heterogeneous. Immunohistochemical staining revealed the prominent presence of von Willebrand factor (VWF) at the sites of platelet accumulation, presence of tissue factor and platelets at the sites of deposition of fibrin fibrils. It also revealed the presence of CD16-, CD45- and CD34-positive cells, yet the functional roles of these cells have still to be elucidated. There are weak positive correlation between the number of inflammatory cells involved in the unit area of coronary thrombi specimen and the time of collection of the specimens after the onset of chest pain. Conclusions:,In spite of various limitations, our results contain information suggesting the possible role of VWF in platelet-thrombus formation, possible important role played by tissue factor and activated platelets in the formation of fibrin fibrils, and the positive relationship between inflammatory cells migration and the formation of occlusive thrombi in human coronary arteries. [source] Dinoflagellate cyst biostratigraphy of the Opalinuston Formation (Middle Jurassic) in the Aalenian type area in southwest Germany and north SwitzerlandLETHAIA, Issue 1 2010SUSANNE FEIST-BURKHARDT Feist-Burkhardt, S. & Pross, J. 2010: Dinoflagellate cyst biostratigraphy of the Opalinuston Formation (Middle Jurassic) in the Aalenian type area in southwest Germany and north Switzerland. Lethaia, Vol. 43, pp. 10,31. In order to provide a detailed dinoflagellate cyst stratigraphy of the Lower Aalenian Opalinuston Formation from the Aalenian type area, 68 samples from four boreholes and one outcrop section were analysed. The sample localities are Hausen an der Fils and Wittnau in southwest Germany, Weiach in north Switzerland and Mont Russelin in the Swiss Jura Mountains. Dinoflagellate cyst assemblages were recovered from the Late Toarcian Aalensis Zone to the Late Aalenian Murchisonae Zone. The samples yielded rich, well-preserved and diverse assemblages with 51 dinoflagellate cyst taxa identified in total. The dinoflagellate cyst distribution data obtained from this study allow a high-resolution biostratigraphical subdivision of the lowermost Middle Jurassic Opalinuston Formation into four palynostratigraphical units. First and last occurrences, acmes and consistent presence of the species Batiacasphaera sp. A, Evansia cf. granochagrinata, Kallosphaeridium praussii, Nannoceratopsis triangulata, Phallocysta? frommernensis and Wallodinium laganum were selected as the criteria for defining these units. The obtained high-resolution palynostratigraphical scheme provides a basis for establishing and further refining early Middle Jurassic biostratigraphy in the Boreal and Tethyan realms. ,Aalenian, biostratigraphy, dinoflagellate cysts, Germany, Jurassic, Switzerland, Toarcian. [source] Disease-specific particles without prion protein in prion diseases , phenomenon or epiphenomenon?NEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 4 2007P. P. Liberski The search for the cause of transmissible spongiform encephalopathies (TSEs) has a long and tortuous history. In a recent paper, 25-nm virus-like particles were identified that were consistently observed in cell cultures infected with Creutzfeldt-Jakob disease (CJD) and scrapie; they are similar to, or even identical with, the virus-like tubulovesicular structures (TVS) found in experimental scrapie as early as in 1968, and subsequently in all naturally occurring and experimentally induced TSEs. These particles have been viewed with caution by the scientific community because of the unverified or uninterpretable record of virus-like structures reported over the years in TSEs. TVS are spherical or tubular particles of approximate diameter 25,37 nm. They are smaller than synaptic vesicles, but larger than many particulate structures of the central nervous system, such as glycogen granules. Their electron density is higher compared with synaptic vesicles, and in experimental murine scrapie, they form paracrystalline arrays. None of these observations distinguish between TVS as an entity critical to the infectious process, or as a highly specific ultrastructural epiphenomenon, but their consistent presence in all TSEs demands further research. [source] | ||||||||||